Nicely written and turns the resolution of a bug into a victory of both discovery of the flaw as well as an deeper appreciation of the design of the language and its advantages of writing solid code with it.

Having written/debugged much C, a very dangerous language for memory structures, examples like this reach to the heart of how to step beyond the theory of use of a language to the practice of use that illustrates both the risks and rewards of a language that improves upon C.